Active Terahertz Nanoantennas Based on VO2 Phase Transition

Frequency tunable near-infrared metamaterials based on VO2 phase transition.

Engineering metamaterials with tunable resonances from mid-infrared to near-infrared wavelengths could have far-reaching consequences for chip based optical devices, active filters, modulators, and sensors. Utilizing the metal-insulator phase transition in vanadium oxide (VO(2)), we demonstrate frequency-tunable metamaterials in the near-IR range, from 1.5 - 5 microns. Arrays of Ag split ring r...

Metal-insulator phase transition in a VO2 thin film observed with terahertz spectroscopy

Metal-insulator Phase Transition in Vo2

-The effects of doping and uniaxial stress on the structural and magnetic properties of V02 are reviewed. Important electron-electron correlation effects are deduced : (i) in the metallic phase from the results obtained in V I ~ N ~ ~ O ~ alloys, (ii) in the insulating phases of pure V02 at ambiant pressure (MI), under uniaxial stress or in the presence of Cr impurities (T and M2). Discovered i...

Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films

Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2...

Active Optical Metasurfaces Based on Defect-Engineered Phase-Transition Materials.

Active, widely tunable optical materials have enabled rapid advances in photonics and optoelectronics, especially in the emerging field of meta-devices. Here, we demonstrate that spatially selective defect engineering on the nanometer scale can transform phase-transition materials into optical metasurfaces. Using ion irradiation through nanometer-scale masks, we selectively defect-engineered th...